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Frequency and Correlation of Nearest Neighboring Nucleotides in Human Genome

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Chinese Journal of Chemical Physics 2009年第1期22卷 27-33页

作者： Neng-zhi Jin zi-xian Liu Wen-yuan Qiu Department of Chemistry State Key Laboratory of Applied Organic Chemistry Lanzhou Universiry. Lanzhou 730000 China

zipf＇s approach in linguistics is utilized to analyze the statistical features of frequency and correlation of 16 nearest neighboring nucleotides （AA, AC, AG, …, TT） in 12 human chro- mosomes （Y, 22, 21, 20, 19, 18, 17, 16, 15, 14, 13, and 12）. It is found that these statistical features of nearest neighboring nucleotides in human genome：（i） the frequency distribution is a linear function, and （ii） the correlation distribution is an inverse function. The coefficients of the linear function and inverse function depend on the GC content. It proposes the correlation distribution of nearest neighboring nucleotides for the first time and extends the descriptor about nearest neighboring nueleotides.

关键词： zipf's law Nearest neighboring nucleotide Frequency distribution Correlation distribution

One-step co-electrodeposition of graphene oxide doped poly(hydroxymethylated-3,4-ethylenedioxythiophene) film and its electrochemical studies of indole-3-acetic acid

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Chinese Chemical Letters 2014年第4期25卷 511-516页

作者： zi-Lan Feng yuan-yuan Yao Jing-Kun Xu Long Zhang zi-Fei Wang Yang-Ping Wen Jiangxi Key Laboratory of Organic Chemistry Jiangxi Science and Technology Normal University College of Science Jiangxi Agricultural University

A novel graphene oxide （GO） doped poly（hydroxymethylated-3,4-ethylenedioxythiophene）（PEDOTM） film has been achieved via one-step co-electrodeposition and utilized for electrochemical studies of indole-3-acetic acid （IAA）. The incorporation of GO into PEDOTM film facilitated the electrocatalytic activity and exhibited a favorable interaction between the PEDOTM/GO film and the phytohormone during the oxidation of IAA. Under optimized conditions, differential pulse voltammetry and square wave voltammetry were used for the quantitative analysis of IAA, respectively, each exhibiting a wide linearity range from 0.6 μmol L-1 to 10 μmol L-1 and 0.05 μmol L-1 to 40 μmol L-1, good sensitivity with a low detection Iimit of 0.087 μmol L-1 and 0.033μmol L T, respectively, as well as good stability. With the notable advantages of a green, sensitive method, expeditious response and facile operation, the as-prepared PEDOTM/GO organic-inorganic composite film provides a promising platform for electrochemical studies of IAA.

关键词： Co-electrodeposition EDOT derivatives Graphene oxide Indole-3-acetic acid

Implementing VLPR systems based on TMS320DM642

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第12期8卷 2005-2016页

作者： ZHU Le-qing ZHANG San-yuan YE Xiu-zi School of Computer Science and Technology Zhejiang University Hangzhou 310027 China

This paper gives a practical schema for using DSP boards to construct Vehicle License Plate Recognition (VLPR) modules that could be embedded in any Intelligent Transportation System (ITS). Using DSP can avoid the heavy investment in dedicated VLPR system and improve the computational power compared to PC software environment. Low cost, high computational power, and high flexibility of DSP provide the License Plate Recognition System (LPRS) an excellent cost-effective solution to execute the major part of the recognition tasks. This paper describes a successful implementation of VLPR system based on Texas Instruments (TI)'s TMS320DM642. The DSP board acquires video (which could be output to a monitor for surveillance) from a camera, captures images from the video, locates and recognizes the license plates in images, and then sends the recognized results and related images after compression to a host PC through the network. Finally, the overall software is optimized according to the features of DM642 chip. Experiments showed that the DSP VLPR system performs well on the local license plates, and that the processing speed and accuracy can meet the requirement of practical applications.

关键词： License Plate Recognition (LPR) Embedded system Image processing DSP DM642

Reliable calculations of nuclear binding energies by the Gaussian process of machine learning

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Nuclear Science and Techniques 2024年第6期35卷 130-144页

作者： zi-Yi yuan Dong Bai Zhen Wang Zhong-Zhou Ren School of Physics Science and Engineering Tongji UniversityShanghai 200092China College of Science Hohai UniversityNanjing 211100China Key Laboratory of Advanced Micro-Structure Materials Ministry of EducationShanghai 200092China

Reliable calculations of nuclear binding energies are crucial for advancing the research of nuclear physics. Machine learning provides an innovative approach to exploring complex physical problems. In this study, the nuclear binding energies are modeled directly using a machine-learning method called the Gaussian process. First, the binding energies for 2238 nuclei with Z > 20 and N > 20 are calculated using the Gaussian process in a physically motivated feature space, yielding an average deviation of 0.046 MeV and a standard deviation of 0.066 MeV. The results show the good learning ability of the Gaussian process in the studies of binding energies. Then, the predictive power of the Gaussian process is studied by calculating the binding energies for 108 nuclei newly included in AME2020. The theoretical results are in good agreement with the experimental data, reflecting the good predictive power of the Gaussian process. Moreover, the α-decay energies for 1169 nuclei with 50 ≤ Z ≤ 110 are derived from the theoretical binding energies calculated using the Gaussian process. The average deviation and the standard deviation are, respectively, 0.047 MeV and 0.070 MeV. Noticeably, the calculated α-decay energies for the two new isotopes ^ (204 )Ac(Huang et al. Phys Lett B 834, 137484(2022)) and ^ (207) Th(Yang et al. Phys Rev C 105, L051302(2022)) agree well with the latest experimental data. These results demonstrate that the Gaussian process is reliable for the calculations of nuclear binding energies. Finally, the α-decay properties of some unknown actinide nuclei are predicted using the Gaussian process. The predicted results can be useful guides for future research on binding energies and α-decay properties.

关键词： Nuclear binding energies decay Machine learning Gaussian process

Biodegradable magnesium-matrix composites:A review

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International Journal of Minerals,Metallurgy and Materials 2020年第6期27卷 724-744页

作者： Jin-long Su Jie Teng zi-li Xu yuan Li College of Materials Science and Engineering Hunan UniversityChangsha 410082China The First Affiliated Hospital Hunan Normal UniversityChangsha 410006China

Biodegradable magnesium alloys as new biomedical implant materials have been extensively studied because of their notable biodegradability over traditional bio-inert ***,the extreme degradation rate of pure magnesium leads to the loss of its mechanical integrity before the tissue recovers *** solutions to this challenge are as follows:(1)purification,(2)alloying,(3)surface modification,and(4)biodegradable magnesium-matrix composites(BMMCs)*** to the tunability of mechanical properties,the adjustability of degradation rate,and the improvement of biocompatibility,BMMCs reinforced with bioactive reinforcements have promising applications as a new generation of biomedical *** this review,the processing methods,Mg matrix,and reinforcement phases of BMMCs are ***,the review comprehensively discusses various BMMCs synthesized thus far,aiming to show the governing aspects of the achieved mechanical properties,corrosion behavior,and ***,this paper also discusses the research direction and further development areas for these materials.

关键词： magnesium-matrix composites biomaterials mechanical properties corrosion behavior

Random vibration of hysteretic systems under Poisson white noise excitations

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Applied Mathematics and Mechanics(English Edition) 2023年第2期44卷 207-220页

作者： Lincong CHEN zi yuan Jiamin QIAN J.Q.SUN College of Civil Engineering Huaqiao UniversityXiamen 361021Fujian ProvinceChina Key Laboratory for Intelligent Infrastructure and Monitoring of Fujian Province Xiamen 361021Fujian ProvinceChina Department of Mechanical Engineering School of EngineeringUniversity of CaliforniaMercedCA 95343U.S.A.

Hysteresis widely exists in civil structures,and dissipates the mechanical energy of *** on the random vibration of hysteretic systems,however,is still insufficient,particularly when the excitation is *** this paper,the radial basis function(RBF)neural network(RBF-NN)method is adopted as a numerical method to investigate the random vibration of the Bouc-Wen hysteretic system under the Poisson white noise *** solution to the reduced generalized Fokker-PlanckKolmogorov(GFPK)equation is expressed in terms of the RBF-NNs with the Gaussian activation functions,whose weights are determined by minimizing the loss function of the reduced GFPK equation residual and constraint associated with the normalization condition.A steel fiber reinforced ceramsite concrete(SFRCC)column loaded by the Poisson white noise is studied as an example to illustrate the solution *** effects of several important parameters of both the system and the excitation on the stochastic response are evaluated,and the obtained results are compared with those obtained by the Monte Carlo simulations(MCSs).The numerical results show that the RBF-NN method can accurately predict the stationary response with a considerable high computational efficiency.

关键词： random vibration Bouc-Wen hysteresis system non-Gaussian excitation Poisson white noise excitation radial basis function(RBF)neural network(RBF-NN)

Modeling of irradiation-induced damage and failure behaviors of fuel foil/cladding interface in UMo/Zr monolithic fuel plates

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Nuclear Science and Techniques 2022年第5期33卷 16-29页

作者： Xiang-Zhe Kong Xiao-Bin Jian Feng Yan Chang-Bing Tang zi-Xuan Guo Shu-Rong Ding yuan-Ming Li Chun-Yu yin Institute of Mechanics and Computational Engineering Department of Aeronautics and AstronauticsFudan UniversityShanghai 200433China Science and Technology On Reactor System Design Technology Laboratory Nuclear Power Institute of ChinaChengdu 610213China

Models to describe the damage and fracture behaviors of the interface between the fuel foil and cladding in UMo/Zr monolithic fuel plates were established and numerically *** effects of the interfacial cohesive strength and cohesive energy on the irradiationinduced thermal-mechanical behaviors of fuel plates were *** results indicated that for heterogeneously irradiated fuel plates:(1)interfacial damage and failure were predicted to be initiated near the fuel foil corner with higher fission densities,accompanied by the formation of a large gap after interface failure,which was consistent with some experimental observations;high tensile stresses in the fuel foil occurred near the edges of the failed interface,attributed to through-thickness cracking of the fuel foil,as found in some post-irradiation examinations;(2)the cohesive strength and cohesive energy of the interface both influenced the in-pile evolution behaviors of fuel plates;a lower cohesive strength or cohesive energy resulted in faster interfacial damage;(3)after interface fracture,the thickness of the whole plate increased to a greater degree(by~20%)than that of the samples without interfacial damage,which was attributed to the locally enhanced Mises stresses and the nearby creep deformations around the cracked *** study provided a theoretical basis for assessing failure in fuel elements.

关键词： UMo/Zr Irradiation-inducedthermo-mechanicalbehavior Numericalsimulation Cohesive model Interfacialfailure

Linear operators and positive semidefiniteness of symmetric tensor spaces

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Science China Mathematics 2015年第1期58卷 197-212页

作者： LUO zi Yan QI Li Qun YE yin Yu State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong University Department of Applied Mathematics The Hong Kong Polytechnic University Department of Management Science and Engineering Stanford University

We study symmetric tensor spaces and cones arising from polynomial optimization and physical *** prove a decomposition invariance theorem for linear operators over the symmetric tensor space,which leads to several other interesting properties in symmetric tensor *** then consider the positive semidefiniteness of linear operators which deduces the convexity of the Frobenius norm function of a symmetric ***,we characterize the symmetric positive semidefinite tensor(SDT)cone by employing the properties of linear operators,design some face structures of its dual cone,and analyze its relationship to many other tensor *** particular,we show that the cone is self-dual if and only if the polynomial is quadratic,give specific characterizations of tensors that are in the primal cone but not in the dual for higher order cases,and develop a complete relationship map among the tensor cones appeared in the literature.

关键词： symmetric tensor symmetric positive semidefinite tensor cone linear operator SOS cone

External Pressure Forming and Buckling Analysis of Tubular Parts with Ribs

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Journal of Materials Science & Technology 2006年第5期22卷 708-712页

作者： Gang LIU Xuelian yin Shijian yuan School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001 China

Buckling and forming processes of tubes with varying slenderness ratio （ratio of length to diameter） under external hydraulic pressure were analyzed with three-dimensional finite element method （FEM） for studying tube external pressure forming （EPF）. Buckling pressures for different tube blanks without mandrel were predicted, and an EPF of a carbon steel tube onto a mandrel with six ribs was simulated. Both thickness distribution and buckling pressure from the simulations were found to be in agreement with those from experiments. Buckling pressures are shown to be a function of the slenderness ratio. The tubular part with six ribs produced by EPF has a uniform thickness distribution, whose maximum thinning rate is only 5.9%.

关键词： External pressure forming Hydroforming Lightweight component Buckling